The present invention relates to a displacement machine for compressible media. In particular to a machine having at least one displacement chamber-arranged in a stationary housing and rendered in the manner of a groove which extends in a spiral shape. There is a band or tongue shaped displacement body associated with each displacement chamber and likewise rendered in spiral shape. The displacement body is held on a discoid rotor, which can be driven eccentrically in relation to the housing and in such a manner that during operation, each of the displacement bodies outside wall points performs a circular movement bounded by the peripheral walls of the displacement chamber. The displacement body's curvature relative to the curvature of the displacement chamber is dimensioned such that it nearly comes in contact with the radially inner and outer peripheral walls of the displacement chamber at one or more continuously advancing lines of sealing. For sealing the radial gap formed between the stationary housing and the rotor, a sheet metal strip having a roughness applied in a precisely targeted fashion, is held on one of the surfaces where the sealing is to occur.
A displacement machine constructed in such a fashion is known, e.g., from DE-OS No. 31 41 525. According to the latter, a seal is produced at least on one of the component surfaces by means of an application of a sheet metal strip with a targeted roughness whose roughness peaks are to be plastically deformable or removable when the machine is first operated. The seal is largely self-adjusting as the components nearly come into contact with one another. Said seal results in a minimal clearance and a favorable labyrinth effect. Since each point of the displacement body in each case collaborates only with precisely defined points of the housing, the deformation or removal process occurring when the machine is first operated results in the setting of a clearance which is optimally adjusted to the prevailing local conditions.